Bimodal cationics for water clarification

ABSTRACT

A polymer admixture comprising a first cationic polymer having a molecular weight between about 2,500-1,000,000 in admixture with a second cationic polymer having a molecular weight between about 1,000,000-50,000,000 wherein said admixture contains a weight ratio of first polymer to second polymer between about 50:1 to 1:50, has greatly improved properties for treating and clarifying waste waters contaminated with oily waste and dispersed solids. The first cationic polymer is preferably a homopolymer, and the second cationic polymer is preferably a copolymer of acrylamide containing the same cationic monomer used to synthesize the first cationic polymer.

INTRODUCTION

The use of cationic polymers to clarify waste waters is known in theart. In addition, cationic polymers have been combined with anionicpolymers to achieve improved results.

However, the use of these combinations of polymers still do not providesufficient clarity when treating waters which are contaminated with oilywaste matter as well as highly dispersed solid materials. These kinds ofwaste waters which are contaminated with oily organic waste matter aswell as highly dispersed solid material, either of an inorganic or anorganic nature or, perhaps, combinations thereof, present what has beento data an impossible task in regards to the geneal cleanup of waterswhich have been contaminated in this manner. Waters of the typementioned above include ground waters found in petroleum recovery oilfields as well as ground waters and waste waters found in the refineryoperations themselves. In addition, these highly contaminated waters mayalso include process waters such as ethylene quench waste water anddrilling mud waste waters.

Any refinery process water, petroleum chemical waste water, ballastwaste water, river water, underground feed water, ethylene quench wastewater, oil-in-water waste emulsions from oil recovery fields, and thelike are difficult contaminated waters requiring chemical treatment andclarification and present extreme difficulty in this treatment andclarification process.

If one were to successfully treat these kinds of waste waters whichcontain oily waste matter as well as dispersed solid matter of anorganic or inorganic nature, one could advance the art of treating andclarifying contaminated waters of this type.

It is, therefore, an object of this invention to disclose a polymeradmixture which successfully treats and clarifies contaminated waterscontaining oily waste matter and dispersed solids of either an organicor inorganic nature.

It is also an object of this invention to treat and clarify these oilywaste and dispersed solid contaminated waters with a combination ofpolymers of a prescribed nature and having a prescribed molecular weightrelationship.

Another object of this invention is to describe a polymer admixturewhich may be used effectively to treat and clarify contaminated wastewasters, wherein said waste waters contain oily waste matter as well asdispersed inorganic or organic solid matter.

It is another object of this invention to describe a particularpolymeric admixture of cationic polymers having a bimodal weight averagemolecular weight distribution and wherein the admixture of polymerscontains a first cationic polymer with a relatively low molecular weightdistribution as well as a second cationic polymer which has a relativelyhigh molecular weight distribution.

THE INVENTION

We have discovered that a combination of cationic polymers having amolecular weight distribution which presents a bimodal molecular weightdistribution of cationic polymers effectively treats and clarifieswaters contaminated with oily waste matter and dispersed inorganicand/or organic solid matter.

The polymer admixture which is effective for treating and clarifyingwaters contaminated with oily waste and dispersed solids comprises:

(a) a first cationic polymer having a weight average molecular weightranging between about 2,500-1,000,000, in admixture with

(b) a second cationic polymer having a weight average molecular weightranging between about 1,000,000-50,000,000,

wherein said polymer admixture contains a weight ratio of a:b rangingbetween about 50:1 to 1:50.

The polymer admixture described above preferably contains a firstcationic polymer which has a weight average molecular weight rangingbetween about 5,000-800,000 and a second cationic polymer having aweight average molecular weight ranging between about5,000,000-35,000,000.

The First Cationic Polymer

The first cationic polymer may be a homopolymer or a copolymer of avinylic cationic monomer or it may be a polymer which has beensynthesized by condensation methods, for example the condensationreaction of ethylene dichloride and ammonia. Preferably, however, thefirst cationic polymer is a homopolymer or a copolymer of a vinyliccationic monomer chosen from the group consisting of DADMAC, DMAEM,DMAEA, MAPTAC, AMPIQ, DEAEA, DEAEM, DMAEAcAm, DMAEMAcAm, DEAEAcAm,DEAEMAcAm, and their acid and quaternized salts.¹

Preferably, the first cationic polymer is a homopolymer of a vinyliccationic monomer, said homopolymer having a weight average molecularweight ranging between about 2,500-1,000,000 and said vinylic cationicmonomer being chosen from the group consisting of DADMAC, MAPTAC, AMPIQ,as well as DMAEM, DMAEA, DEAEM, DEAEA, DMAEAcAm, DEAEAcAm, DMAEMAcAm,DEAEMAcAm, and their acid and quaternized salts and the like.

Most preferably, the first cationic polymer is a homopolymer of avinylic cationic monomer chosen from the group consisting of DADMAC,MAPTAC, DMAEM, DMAEA, and their acid and quaternized salts, and having amolecular weight ranging between about 5,000-800,000.

As stated before, the first cationic polymer may also be a condensationpolymer. The cationic condensation polymers are represented by thosepolymers achieved by adding closely controlled stoichometric quantitiesof difunctional or multifunctional chemicals to one another in a mannerwhich would condense at a common nitrogen atom to form multi-chainedmolecules. Examples of such condensation polymers include, but are notlimited to, the condensation reaction between ethylene dichloride andammonia, the condensation reaction between ethylene dichloride andmethylamine, the condensation reaction between epichlorohydrin anddimethylamine, the condensation reaction between epichlorohydrin,ethylene oxide or propylene oxide, and ammonia or otheralkyl-substituted amine compounds, and the like.

When the first cationic polymer is a condensation polymer, it ispreferred that the condensation polymer have a molecular weight withinthe range of about 2,500-1,000,000 and, preferably, in the range ofabout 2,500-500,000.

The Second Cationic Polymer

The second cationic polymer normally has a weight average molecularweight ranging between about 1,00,000-50,000,000. Preferably, the secondcationic polymer has a weight average molecular weight ranging betweenabout 5,000,000-35,000,000 and is a copolymer of either acrylamide ormethacrylamide with a vinylic cationic monomer chosen from the groupconsisting of DADMAC, DMAEM, DMAEA, MAPTAC, AMPIQ, DEAEA, DMAEAcAm, DMAEmethAcAm, and their acid and quaternized salts. In another preferredembodiment, the second cationic copolymer of acrylamide ormethacrylamide has a weight average molecular weight ranging betweenabout 5,000,000-35,000,000 and is a copolymer of either acrylamide ormethacrylamide with the same vinylic cationic monomer which is containedin the first cationic polymer.

The Admixture

The polymer admixture which is used for treating and clarifying waterscontaminated with oily waste and dispersed solids normally comprises;

(a) a first cationic homopolymer of a vinylic cationic monomer, saidhomopolymer having a weight average molecular weight ranging betweenabout 2,500-1,000,000, in admixture with

(b) a second cationic copolymer of acrylamide with the identical vinyliccationic monomer used in the homopolymer above, said copolymer having aweight average molecular weight ranging between about1,000,000-50,000,000,

wherein said polymer admixture contains the first cationic homopolymerand second cationic copolymer in the weight ratio ranging between about50:1 to about 1:50.

The polymer admixture most useful for treating and clarifying waterscontaminated with oily waste and dispersed solids comprises ahomopolymer of a vinylic cationic monomer chosen from the groupconsisting of DADMAC, MAPTAC, DMAEM, DMAEA, and their acid andquaternized salts in admixture with a copolymer of acrylamide with avinylic cationic monomer chosen from the group consisting of DADMAC,MAPTAC, DMAEM, DMAEA, and their acid and quaternized salts, and whereinthe homopolymer has a weight average molecular weight between about2,500-1,000,000 and the copolymer has a weight average molecular weightbetween about 1,000,000-50,000,000, and wherein the weight ratio ofhomopolymer to copolymer is between about 50:1 to 1:50.

In a preferred embodiment, the polymer admixture contains a homopolymerand a copolymer which are synthesized using the same vinylic cationicmonomer. The homopolymer may, for example, be a polyDADMAC, apolyMAPTAC, a polydimethylaminoethylmethacrylate, apolydimethylaminoethylmethacrylate sulfate salt or apolydimethylaminoethylacrylate, or a polydimethylaminoethylacrylatesulfate salt or a polydimethylaminoethylmethacrylate methyl chloridequaternary salt, a dimethylaminoethylacrylate methyl chloride salt, andthe like. When the quaternized or acid salts of these types of vinyliccationic monomers are used, it is to be understood that the homopolymerand/or the copolymer of these salts may be originally made using thenon-quaternized materials followed by quaternization with standardquaternizing agents such as methylchloride, methylbromide,dimethylsulfate, or salted with HCl, H₂ SO₄, acetic acid or the like,after the polymerization has been completed.

In addition to the quaternizing agents mentioned above, amine containingmonomers which have not been quaternized may still be positively chargedby neutralization with organic or inorganic acids such as HCl, H₂ SO₄,acetic acid, nitric acid, and the like. When this neutralization occurs,the basic nitrogen in the monomer is positively charge by reacting witha free proton from the acid moiety used to accomplish theneutralization. In a similar fashion, these same acids and quaternizingagents may be used to form cationic monomers which are subsequentlypolymerized to form either the homopolymer or the copolymers of thisinvention.

The admixture may be made either by polymerizing the homopolymerseparately and admixing with a copolymer manufactured separately, orthey may be made in a sequential manner. The weight ratio of homopolymerto copolymer is preferably between about 50:1 to 1:50 and is mostpreferably between about 10:1 to 1:10. The polymers of this inventionmay be synthesized as solution polymers, condensation polymers,water-in-oil emulsion polymers as in Anderson/Frisque, U.S. Pat. No. Re.28,474 and U.S. Pat. No. Re. 28,576, and may be used as such, or may beadmixed in a separate step to achieve the compositions of thisinvention.

In addition, the polymer admixture used to treat and clarify badlycontaminated waters containing oily waste matter and dispersed organicor inorganic solids may also advantageously contain multivalent metallicsalts such as ferrous or ferric chloride, aluminum chloride, zincchloride, manganese nitrate, magnesium chloride, calcium chloride, andthe like. The choice of anion is immaterial and is made primarily on aneconomic basis. Chloride salts are preferred but nitrate, sulfate,phosphate anion may be present if the corresponding multivalent metallicsalt is sufficiently water-soluble.

The addition of these multivalent metallic salts may derive even moreimprovement of water qualities when used in admixture with the cationicpolymer admixtures of this invention. To better describe and exemplifythe inventions contained within this disclosure, the following examplesare presented.

In all of the examples to follow, the following Glossary shall apply tothe identification of the materials used.

    ______________________________________                                         GLOSSARY                                                                     ______________________________________                                        M           =     1,000                                                       MM          =     1,000,000                                                   AcAm        =     Acrylamide                                                  DMAEM       =     Dimethylaminoethylmethacrylate                              HMDA bttms  =     Hexamethylenediamine tower bottoms                                            residue                                                     epi         =     epichlorohydrin                                             MO--epi     =     cross-linking agent containing ethylene                                       oxide/propylene oxide condensation                                            polymer having molecular weight                                               between 100-5000, finally capped with                                         epichlorohydrin.                                            DMAEM DMS   =     Dimethylaminoethylmethacrylate                              quat.             quaternized with dimethyl sulfate.                          DACHA Hcl   =     Diallylcyclohexylamine hydrochloride                        TEA         =     Triethanolamine                                             HMDA        =     Hexamethylene diamine                                       NH.sub.3    =     ammonia                                                     EDC         =     1,2 ethylene dichloride                                     DADMAC      =     Diallyl dimethyl ammonium chloride                          DMAEA       =     Dimethyl aminoethyl acrylate and/or its                                       acid salts                                                  MAPTAC      =     Methacrylamidopropyl trimethyl                                                ammonium chloride                                           AMPIQ       =     1-acrylamido-4-methyl piperazine                                              (quaternized with MeCl, MeBr, or                                              Dimethyl Sulfate)                                           DEAEA       =     Diethylaminoethyl acrylate and/or its                                         acid salts                                                  DEAEM       =     Diethylaminoethyl methacrylate and/or                                         its acid salts                                              DMAEAcAm    =     Dimethylaminoethyl acrylamide and/or                                          its acid salts                                              DMAEMAcAm   =     Dimethylaminoethyl methacrylamide                                             and/or its acid salts                                       DEAEAcAm    =     Diethyl aminoethyl acrylamide and/or                                          its acid salts                                              DEAEMAcAm   =     Diethyl aminoethyl methacrylamide                                             and/or its acid salts                                       Activity    =     weight % of active polymeric                                                  ingredient                                                  ______________________________________                                    

                  TABLE I                                                         ______________________________________                                        Com-                       Molecular Weight/                                  pound Chemical Description Activity                                           ______________________________________                                        A     Copolymer of AcAm                                                                             30-35%   5-15 MM;                                             and DMAEM H.sub.2 SO.sub.4                                                                    70-65%   30-35% active                                        salt                                                                    B     Copolymer of AcAM                                                                             30-35%   5-15 MM;                                             and DMAEM DMS   70-65%   28-32% active.                                       quat                                                                    C     (a)   Condensate polymer (a) 3-5 M; 35-37%                                          HMDA/epi/          active                                                     MO--epi                                                                 (b)   AcAm--DACHA        (b) 5-10 M; 35-37%                                         copolymer a:b = 3:1                                                                              active                                         D     TEA condensate       3-5 M; 56% active                                        quaternized with MeCl                                                   E     Compound D + ZnCl.sub.2                                                                            65% active                                               at weight ratio                                                               40:50 3-5 M;                                                            F     HMDA/epi             3-5 M; 40% active                                        HCl salt                                                                G     F + ZnCl.sub.2       3-5 M; 40% active                                        2:3 weight ratio                                                        H     NH.sub.3 /EDC +      3-10 M; 23% active                                       AlCl.sub.3 at 1:2 ratio                                                 I     H.sub.2 O solution homo-                                                                           500-800 M; 10%                                           polymer of DMAEM     active                                                   H.sub.2 SO.sub.4 salt                                                   J     TEA condensate       3-5 M; 35% active                                        HCl salt                                                                K     88% Compound I       500-800 M;                                               formulation 3%       5-15 MM                                                  Compound A formula-                                                           tion Remainder-diluents                                                                            about 10-15%                                             & inert salts        actives                                            ______________________________________                                    

Using the polymers described above, tests were conducted on waterscontaminated with oil and solid materials, both of an organic andinorganic nature, where such waters were clarified by the chemicalsand/or combination of chemicals described.

Three types of contaminated waters were tested. The first type istypical oil field contaminated ground waters which normally appear inthe oil-in-water emulsion form where said oil-in-water emulsion iscontaminated by suspended organic and/or inorganic materials as well(referred to herein as "Produced Waters").

The second type of contaminated waters which were tested came from anethylene quench process waste water derived from an industrial plant inthe southwest part of the United States.

The third type of contaminated water was derived from an oil fieldoperation which had been using various types of drilling mudformulations in the process of drilling for gas and/or oil.

The types of tests used were standard bottle tests or jar tests whereina prescribed amount of active polymeric ingredient was added to thewaste waters to be tested, shaken for a prescribed amount of time, andrated by the ability of the treated contaminated water to separate intophases which would allow decantation, filtration, or other means forseparating the contaminations from the treated water.

In addition, three types of tests were run on each of the fluids. Theywere classified as bottle tests, jar tests, and a WEMCO test.

In the bottle test, contaminated water is added to a series of cappedbottles to which then is added prescribed quantities of test solutionscontaining the active polymer ingredients of this invention. The bottlesare capped and agitated, using a slow rolling mechanism, for a period ofrevolutions or for a prescribed constant number of shakes. Afteragitation, the bottles are set on a flat surface and water clarity andcoagulation efficiency visually observed as a function of time. Anumerical system ranging between 1-10 is used to rate the bottles with 1being the best water quality and rate of and/or degree of coagulationand 10 being the worst. Finally, the bottles are agitated vigorouslywith from 50-100 vigorous rolls or shakes. Again, the bottles are set onflat surfaces and observed to record clarity of water and the speed anddegree of coagulation. Again, the rating system between 1-10 is usedwith 1 being the best water quality, or best speed and degree ofcoagulation, and 10 being the worst.

When these contaminated waters are jar tested, the procedure is normallyto obtain fresh samples of contaminated waters of whatever kind and addto a series of 1000 milliliter beakers about half the total beakervolume of the ground waters or contaminated waters to be tested. Thesebeakers are placed under paddles provided by a gang stirrer kit and thepaddles lowered into the fluid and each beaker stirred under exactly thesame agitation conditions. Agitation is continued for approximately 3minutes after which time the agitation speed is normally reduced toallow for coagulation and phase separation. The fluid contained in thebeakers is examined for the rate of phase separation, the appearance offloc and the speed of formation of the floc, relative size anduniformity of floc formation, speed of settling after agitation isstopped, the clarity or lack of clarity of the supernatant fluids, andthe like. Prior to beginning agitation or immediately following thestart of the initial vigorous agitation, the desire amount of treatmentchemical is added by means of pipette to each of the beakers.

The WEMCO test uses an electric motor which admixes the contaminatedwater with various kinds of dispersion gases, normally nitrogen and/orstandard air, and accomplishes an aeration of the sample under excessiveand vigorous agitation provided by the electric motor and rotary shaftwith attached agitator blades. During the operation, samples ofcontaminated water are drawn into the WEMCO agitator system, vigorouslyadmixed with dispersion gases, and pumped from the chamber in which theadmixture is occurring into various beakers, jars, or bottles whichallow a quiescent period for settling and coagulation to be measured.Treatment chemical is added as the contaminated water is drawn into thereaction chamber prior to the addition of dispersion gases orsimultaneously with the addition of dispersion gases. A tachometer ontop of the WEMCO unit is set at a proper RPM which may vary from about900 to about 1800 RPM's depending on the fluid being tested and otherconditions of the test. The agitation chamber normally is a clean glassbowl of approximately 2500-5000 milliliter capacity. Observationsinclude how quickly foam forms and the general characteristics of thefoam which may form. Observations also include how fast oil and solidsbegin forming and coagulating in a ring around the shaft cylinder whichgreets the water surface within the mixing bowl. After agitation forabout 60 seconds, the electrical motor is switched off and thecontaminated water is allowed to remain static without agitation foranother 60 seconds. Again, observations are made to determine foamformation, foam breakage, oil coagulation, and coagulation of othercontaminating solid material dispersed within the original contaminatedwater sample. After 60 seconds, a sample of the treated waters are takenby using a metal or plastic syringe from about 1/2 to about 1/4 inchfrom the bottom of the rounded portion of the agitation bowl. This"thief" sample is placed in a clean bottle and examined closely forclarity. This sample may also be tested analytically for % transmissionusing a standard photoelectric device standard in the industry.

In the following Tables, a "produced water" is a standard oil fieldcontaminated water normally having an oil-in-water waste emulsioncharacter in which solid matter is also suspended. The solid matter maybe of an organic and/or inorganic nature. Table II presents test resultsfor the ratings achieved by bottle testing a standard produced waterhaving various treatments. These treatments indicate the benefits of thecombination polymer treatment described in this invention. Table III isa WEMCO test procedure, again using the same "produced water" as appearsin Table II. Again, as can be seen, a blend of polymers as describedabove provides drastically improved water quality and coagulationresults.

Table IV tests an ethylene quench water derived from an ethylene quenchprocessing operation which was occurring in an oil refinery and chemicalprocessing plant located in the southwestern part of the United States.This ethylene quench water was treated by the jar test proceduredescribed above and ranked in the way prescribed in the Table. Again,the combination polymers of this invention indicate the improved resultsdescribed in this invention.

Table V presents results which show the benefits of various blends ofmaterials when treating drilling muds which had been diluted at a ratioof about 1:50 of drilling mud to water in the standard jar testdescribed above.

In addition, Table VI contains data obtained on actual oil field"produced waters" from an oil recovery facility in the far westernUnited States to test and evaluate a combination of cationic polymersdescribed and claimed herein.

In addition to the data presented above, applicant anticipates that hiscationic polymeric admixture and the method of using said admixture toclarify waste waters contaminated with oily waste and/or suspendedmatter or dispersed matter of an organic or inorganic nature might besynthesized from homopolymers and/or copolymers ofdiallyldimethylammonium chloride, methacrylamido propyl trimethylammonium chloride, and the like.

If one were to synthesize a homopolymer of DADMAC having a molecularweight ranging between about 2500-500,000 or 1,000,000, and admix thishomopolymer with a copolymer of DADMAC and acrylamide or methacrylamidehaving a molecular weight ranging between 1,000,000-50,000,000 and,preferably, between about 5,000,000-35,000,000, and then treatcontaminated waste waters described above with from 0.1-50 ppm of thisadmixture containing DADMAC, with the weight ratio of homopolymer tocopolymer ranging between 50:1 to 1:50, one would expect to see improvedresults from the treatment of this admixture over the simple treatmentwith either of the ingredients of the admixture.

The same would be true if polymers containing MAPTAC were synthesizedand admixed in a similar fashion as long as the treatment levels arethose described above and the molecular weights and ratios ofhomopolymer to copolymer are those described above. In a similarfashion, improvements would be expected in the above polymer admixturesif these polymer admixtures contained additionally multivalent metallicsalts such as iron salts, aluminum salts, zinc salts, mixtures thereof,and the like.

                  TABLE II                                                        ______________________________________                                        Oil-in-Water Waste Emulsions Ground Waters                                    Produced Water Bottle Test                                                                 Rating                                                                              100     100   100                                          Formula                                                                              Ratio       Shakes  Shakes                                                                              Shakes                                                                              100 Shakes                             ______________________________________                                        Blank  0      ppm        10    10    10    10                                 A      0.3               10     9.sup.-                                                                             9.sup.-                                                                             9.sup.-                           A      0.35              10     9.sup.-                                                                             9.sup.-                                                                             9.sup.-                           B      0.3               10    10     9.sup.-                                 C      10                8     5     3     3                                  C      9.7                                                                    blended                  9     5      3.sup.+                                                                             3.sup.+                           A      0.3                                                                    D      12.0               7    7     7     7                                  D      11.65                                                                  blended                   7    7     7     6                                  A      .35                                                                    E      10.0              7      5.sup.+                                                                            2      2.sup.+                           E      9.7                                                                    blended                                                                       A      0.30              6      2.sup.+                                                                            1      1.sup.+                           F      10     ppm        4      2.sup.-                                                                             2.sup.+                                                                            1                                  F      9.7                                                                    blended                  4      2.sup.-                                                                             2.sup.+                                                                            1                                  A      0.3                                                                    G      12                 6    6     5                                        G      11.65                                                                  blended                                                                       A      0.35              5     4     3                                        H      10                10    10    9     8                                  H      9.7                                                                    blended                  9     9     8     7                                  A      0.3                                                                    Blank  0                 10    10    10                                       B      0.3               10     9.sup.-                                                                             9.sup.-                                 A      10                9     5     3                                        A      9.7                                                                    blended                  8     4      2.sup.+                                 B      0.3                                                                    E      10                8     7     4                                        E      9.7                                                                    blended                                                                       B      0.3               6     5      4.sup.+                                 ______________________________________                                    

                  TABLE III                                                       ______________________________________                                        Produced Water                                                                WEMCO Test Procedure Water                                                    Formula        Ratio     % Trans.                                             ______________________________________                                        Blank          0             50                                               A              .36    ppm    51                                               D              12            75                                               D              11.64                                                          blended                      84                                               A              .36                                                            I              12.0          89                                               I              11.64                                                          blended                      98                                               A              .36                                                            G              12            61                                               G              11.64                                                          blended                      63                                               A              .36                                                            ______________________________________                                    

                  TABLE IV                                                        ______________________________________                                        Ethylene Quench Water (Jar Test)                                              (10 = Worst, 1 = Best)                                                        Formula                                                                              Ratio          Rating                                                  ______________________________________                                        Blank  0              7                                                       A      0.3            7     no improvement over blank                         B      0.3            7     no improvement over blank                         I      10             5                                                       I      9.7                                                                    blended               4                                                       A      0.3                                                                    I      9.7                                                                    blended               4                                                       B      0.3                                                                    F      10             4                                                       F      9.7                                                                    blended               3                                                       A      0.3                                                                    F      9.7                                                                    blended                4.sup.+                                                B      0.3                                                                    D      10             4                                                       D      9.7                                                                    blended                4.sup.-A                                                                           0.3                                               D      9.7                                                                    B      0.3            4                                                       E      10             2                                                       E      9.7                                                                    blended               2                                                       A      0.3                                                                    J      10              5.sup.+                                                J      9.7                                                                    blended               4.sup.-                                                 A      0.3                                                                    ______________________________________                                    

                  TABLE V                                                         ______________________________________                                        Drilling Mud                                                                  10 mls Mud in 500 mls Water                                                   (Jar Test)                                                                    Formula    Ratio                Rating                                        ______________________________________                                        A          3      ppm             10                                          Alum       100    ppm             2                                           Alum       97     ppm                                                         blended                           2+  large floc                              A          3      ppm                                                         HCl        100    ppm             3+                                          HCl        97     ppm             3   large floc                              blended                                                                       A          3      ppm                                                         Alum       97     ppm             2   large floc                              blended                                                                       B          3      ppm                                                         ______________________________________                                    

                  TABLE VI                                                        ______________________________________                                        " Produced Water"                                                             Coagulation and Clarification                                                 Oil Field Ground Waters                                                       Actual Tests following Commercial WEMCO Units                                             Treatment Ratio                                                                            Rating                                               Treatment   ppm actives  (1 = Best, 10 = Worst)                               ______________________________________                                        Blank       0                10                                               Polymer I   2.5              9                                                Polymer I   5.0              9                                                Polymer I   10.0             9                                                Polymer I   20.0             7                                                Polymer A   2.5              2                                                Polymer A   5.0              1                                                Polymers A & I(K)                                                                         5.0              4                                                Polymers A & I(K)                                                                         10.0             1.sup.+                                                                             clearly superior                           Polymer A + I(K)                                                                          10.0   (duplicate)                                                                             1.sup.+                                                                             clearly superior                           Blank       0                10                                               Polymer I   1.0              4                                                Polymer I   2.0              2                                                Polymer I   3.0              2.sup.+                                          Polymer I   5.0              1                                                Polymers A + I(K)                                                                         1.0              2.sup.+                                          Polymers A + I(K)                                                                         2.0              1                                                Blank       0                10                                               Polymer I   1.0              5                                                Polymer I   2.0              1-2                                              Polymer I   3.0              1                                                Polymer K (A + I)                                                                         1.0              4-5                                              Polymer K (A + I)                                                                         2.0              1                                                Polymer K (A +  I)                                                                        3.0              1.sup.+                                          Polymer A   1.0              1-2                                              (different loading)                                                           Polymer J*  1.0              5                                                Polymer J   2.0              3                                                Polymer J   3.0              2                                                Blank       0                10                                               Polymer I   1.0              2.sup.+                                          Polymer I   2.0              1                                                Polymer K   1.0              1                                                Polymer J   1.0              5                                                Polymer J   2.0              2.sup.-                                          Polymer J   3.0              1-2                                              Polymer K   1.0              3.sup.+                                          Polymer K   2.0              1-2                                              Polymer K   3.0              1 +   clearly superior                           Blank       0                10                                               Polymer I   1.0              8                                                Polymer I   2.0              3                                                Polymer I   3.0              2-3                                              Polymer I   5.0              1-2                                              Polymer K   1.0              5.sup.+                                          Polymer K   2.0              2-3                                              Polymer K   3.0              1.sup.+                                                                             clearly superior                           ______________________________________                                         *Polymer J = 90%-92% of 16% DMAEM sulfate salt homopolymer, MW = 100,000      8-10% of copolymer DMAEM sulfate salt --AcAm, MW = 5-15 MM               

Having thus described our invention, we claim:
 1. A method ofcoagulating and clarifying waste waters contaminated with oils andsuspended inorganic and/or organic solids which comprises the steps:I.Adding to said waste waters an effective amount of a cationic polymeradmixture comprising:a. a first water-soluble cationic homopolymer of avinylic cationic monomer chosen from the group consisting ofdiallyldimethyl ammonium chloride, dimethylaminoethyl methacrylate andits acid or quaternary salts, methacrylamidoproply trimethyl ammoniumchloride and 1-acrylamido-4-methyl piperazine, N-methyl quaternary salt,said homopolymer having a weight average molecular weight rangingbetween about 2,500-800,000, in admixture with, b. a secondwater-soluble cationic copolymer of acrylamide and a vinylic cationicmonomer chosen from the group consisting of diallyldimethyl ammoniumchloride, dimethylaminoethyl methacrylate and its acid or quaternarysalts, methacrylamidopropyl, trimethyl ammonium chloride and1-acrylamido-4-methyl piperazine, N-methyl quaternary salt, said secondcationic copolymer having a weight average molecular weight rangingbetween about 1,000,000-50,000,000, wherein said polymer admixturecontains a:b within a weight ratio of about 50:1 to 1:50, and therebyforming a treated waste water, and then, II. vigorously agitating saidtreated waste water with or without admixture of a dispersion gas, andthen, III. allowing phase separation to occur forming a clarified waterphase and a coagulated waste phase containing oils and suspendedinorganic and/or organic solids, and then, IV. recovering and reusingsaid clarified water and either recycling said waste phase or discardingor destroying said waste phase.
 2. The method of claim 1 wherein theeffective amount of the cationic polymer admixture ranges between about0.1-50.0 ppm of admixture based on total weight of waste waters.
 3. Themethod of claim 1 wherein the cationic polymer admixture comprises:a. afirst cationic homopolymer having a weight average molecular weightranging between about 5,000-800,000, in admixture with b. a secondcationic copolymer of acrylamide with a vinylic cationic monomer, saidcopolymer having a weight average molecular weight ranging between about5,000,000-35,000,000, and wherein said admixture contains a:b within theweight ratio of 10:1 to 1:10.
 4. The method of claim 3 wherein thevinylic cationic monomer for the homopolymer and the copolymer is thesame and is chosen from the group diallyl dimethyl ammonium chloride,dimethylaminoethyl methacrylate and its acid or quaternary salts, andmethacrylamidopropyl trimethyl ammonium chloride.
 5. The method of claim1 wherein the cationic polymer admixture also contains water-solublesalts of multivalent metallic cations from the group consisting offerrous ion, ferric ion, aluminum ion, cupric ion, zinc ion, manganeseion, calcium, magnesium, and chromic ions, and the like.